Antimicrobial gloves and a method of manufacture thereof

ABSTRACT

Antimicrobial protection may be provided to protective gloves by mixing an antimicrobial agent in a glove material plastisol so that the antimicrobial agent migrates to the exposed surfaces of the gloves when the agent on the glove surface has been depleted. Antimicrobial gloves suitable for use in the food industry may be manufactured using a cold dip process with a plastisol that includes the following weight percentages of (a) a polymer resin, such as polyvinyl chloride (PVC), polypropylene polyethylene (PE), or polyurethane, 43 to 53%, (b) a plasticizer, such as DINP, 43 to 53%, (c) a stabilizer, such as CaZn, 2.7 to 4.7%, and (d) triclosan (2,4,4&#39;-trichloro-2&#39;-hydroxydiphenyl ether), 0.3 to 1.0%.

BACKGROUND OF THE INVENTION

The present invention relates to antimicrobial gloves and a method ofmanufacturing such gloves, and more particularly to antimicrobial glovesfor food handlers that are made of triclosan and polyvinyl chloride(PVC), where the gloves are formed by cold dipping glove molds in aplastisol of PVC, triclosan, a plasticizer and a stabilizer.

The food industry is concerned about bacterial contamination and workersin the industry are frequently required to wear protective gloves toreduce the likelihood that the bacteria from their hands will betransmitted to food. However, the protective gloves may pick upcontaminating bacteria from food or work surfaces they touch, therebysignificantly reducing the effectiveness of the gloves the longer theyare worn. A solution, albeit a costly one, is to have the workers changeor disinfect their gloves frequently. The food industry would prefer amore workable and cost effective solution.

The gloves used by the food industry are typically made of polyvinylchloride (PVC), are seamless to reduce the risk of seam failure, andmeet federal standards for thickness, strength, elasticity, deformation,etc. Gloves of other materials have been tried, but they either do notmeet the federal standards or are not acceptable to the food industry(e.g., high cost, not seamless, difficult to don and remove,uncomfortable to wear, etc.).

Seamless PVC gloves are typically made by dipping glove molds in a lowviscosity PVC plastisol (a liquid mixture of the glove material thatgels to form the gloves), and machines for dipping the glove molds arewell known in the art.

Antimicrobial agents are well known and it would be desirable to provideprotective gloves used in the food industry with an antimicrobial agentthat provides long lasting protection. However, the industry had beenunable to find an antimicrobial agent that meets federal standards forfood handling, that can be used with PVC gloves, and that willeffectively reduce the risk of bacterial contamination during prolongedwear of the gloves carrying the agent. For example, conventional PVCgloves may be dusted with an antimicrobial agent, but the agent wouldnot be effective for prolonged periods because it would rub off duringuse and disappear completely when the gloves are immersed in water.

A potential solution is to mix an antimicrobial agent into a plastisol.For example, U.S. Pat. No. 5,091,442 issued Feb. 25, 1992 to Milnersuggests that an antimicrobial agent, such as triclosan, may be mixedwith a natural rubber latex plastisol to provide antimicrobialprotection for a tubular article such as a condom or catheter. However,the effectiveness of the antimicrobial agent in the article will stilldiminish during use because the agent will gradually disappear from thesurface of the article and will not be replenished. That is, thetriclosan will be removed from the surface of the natural rubber latexlong before the latex wears down to expose the triclosan in the interiorthereof. The nature of the natural rubber latex prevents theantimicrobial agent from migrating to the exposed surface of the latexfrom its interior. This limitation may be acceptable where the articlemakes a single contaminating contact, but is not acceptable for glovesthat will have numerous contacts with diverse potential contaminants.

The Milner patent mentions that PVC may be used instead of the naturalrubber latex, but does not suggest how this is to be done. The methoddisclosed relates only to natural rubber latex, and the differencesbetween latex and PVC preclude the application of the disclosed methodto PVC.

It has also been suggested that an antimicrobial agent may be added to aplastic or polymeric film material, such as PVC, that is used to make asurgical drape sheet. The structure of the PVC allows some antimicrobialagents to migrate to the exposed surface of the drape from the interiorthereof when the agent has been removed from the surface (see U.S. Pat.No. 5,069,907 issued Dec. 3, 1991 to Mixon, et al.). However, theprocess and the plastisol used therewith for making a sheet of plasticor polymeric material are not suitable for dipping gloves. In the sheetmaking process a high viscosity paste is extruded through a sheet feederat high temperature. As discussed above, the glove dipping process usesa low viscosity plastisol.

Accordingly, it is an object of the present invention to provide novelprotective gloves and a method of making protective gloves that obviatethe problems of the prior art.

It is another object of the present invention to provide novelprotective gloves and a method of providing antimicrobial protection tosuch gloves in which an antimicrobial agent in the glove materialmigrates to the exposed surfaces of the gloves when the agent at theglove surface has been depleted.

It is yet another object of the present invention to provide a novelmethod of making seamless protective gloves for the food industry from aplastisol that includes triclosan and PVC.

It is still another object of the present invention to provide a novelmethod of making protective gloves in which triclosan antimicrobialagent is mixed with a PVC plastisol before the gloves are formed by acold dip process whereby the triclosan migrates to the exposed surfacesof the gloves when the triclosan at the surface has been depleted.

These and many other objects and advantages of the present inventionwill be readily apparent to one skilled in the art to which theinvention pertains from a perusal of the claims, the appended drawings,and the following detailed description of preferred embodiments.

DESCRIPTION OF PREFERRED EMBODIMENTS

Antimicrobial protection may be provided to protective gloves by mixingan antimicrobial agent with a glove material plastisol, the agent andplastisol being selected so that the antimicrobial agent migrates to theexposed surfaces of the gloves when the agent at the glove surface hasbeen depleted.

The antimicrobial agent is preferably triclosan and the glove materialplastisol preferably includes a polymer, such as PVC, polypropylenepolyethylene (PE), or polyurethane. The plastisol preferably includes 43to 53% polymer by weight and 0.3 to 1.0% triclosan by weight.

Triclosan (2,4,4'-trichloro-2'-hydroxydiphenyl ether) is a broadspectrum antimicrobial agent that is commercially available under thename Microban™ (Clinitex Corp.) and is suitable for use in the foodindustry.

Antimicrobial gloves suitable for use in the food industry may bemanufactured using a cold dip process with a plastisol that includes thefollowing weight percentages of (a) a PVC resin, 43 to 53%, (b) aplasticizer, 43 to 53%, (c) a stabilizer, 2.7 to 4.7%, and (d)triclosan, 0.3 to 1.0%.

The plasticizer may be any suitable product that has been approved foruse in the food industry, such as di-isonoyphthalate (DINP). Otherphthalate ester plasticizers, such as DIOP, DEOP and DEHP, may be usedfor other glove applications where use of the plasticizer has not beenrestricted. The stabilizer may be any suitable product that has beenapproved for use in the food industry, such as CaZn.

In a preferred embodiment, the plastisol includes 48% PVC resin (weightpercentage), 48% DINP plasticizer, 3.7% CaZn stabilizer, and 0.3%triclosan.

In another embodiment the polymer is polypropylene polyethylene (PE).Test results indicate that the effectiveness of the antimicrobial agentis improved when mixed with a PE plastisol because the agent migrates tothe surface of the gelled PE plastisol more quickly. PE gloves may findsignificant applications in a number of areas, although at present thecost may be high for use in the food industry.

The gloves may be formed using a conventional cold dipping process, suchas described in Plastics Engineering Handbook, page 402 (Society of thePlastics Industry, Inc., 1976). As explained therein, in a cold dippingprocess a cold or room temperature mold is dipped into a plastisol,removed from the plastisol and fused. The thickness of the coatingdepends upon the low-shear-rate viscosity and the yield value of theplastisol. The viscosity and yield value of the plastisol are desirablybalanced so that the plastisol flows well enough to form a uniformcoating and yet does not drip. The plastisol disclosed herein provides aviscosity and yield value balance suitable for making protective gloves.

Conventional mechanical dipping devices may be used. For example,multiple glove forms (e.g., thousands of glove forms) may be carried bya conveyor through the stages in the cold dip process.

In a preferred embodiment, the glove forms may be cold dipped into theplastisol when the forms are about 30° C. warmer than the plastisol, theplastisol being at about 32° C. The gloves remain in the plastisol forabout 15 seconds and are thereafter removed and cured by heating toabout 240° C. for about five minutes. The cured gloves are cooled atabout 66° C. for about fifteen minutes, and thereafter removed from theforms. The glove material is about 0.127 millimeters thick and thegloves are suitable for use in a variety of applications.

The gloves provide effective antimicrobial protection for gloves for thefood industry, meeting all applicable federal regulations. During use,as the antimicrobial agent at the surface of the material wears off, theagent in the material migrates to the surface to provide continuedprotection.

While preferred embodiments of the present invention have beendescribed, it is to be understood that the embodiments described areillustrative only and the scope of the invention is to be defined solelyby the appended claims when accorded a full range of equivalence, manyvariations and modifications naturally occurring to those skilled in theart from a perusal hereof.

What is claimed is:
 1. An antimicrobial protective glove having anantimicrobial agent homogeneously distributed in a material from whichthe glove is formed, and in which the agent migrates to the exposedsurface of the glove to restore the antimicrobial effect when the agentat the exposed surface has been removed, the glove material comprisingby weight percent:polyvinyl chloride, 48%; a plasticizer, 48%; astabilizer, 3.7%; and triclosan, 0.3%, wherein said triclosan internalto the glove material will migrate to the surface of the glove when saidtriclosan at the surface of the glove is removed.
 2. The glove of claim1 wherein said plasticizer is DINP.
 3. The glove of claim 1 wherein saidstabilizer is CaZn.
 4. The glove of claim 1 wherein said glove isseamless.
 5. An antimicrobial protective glove having an antimicrobialagent homogeneously distributed in a material from which the glove isformed, and in which the agent migrates to the exposed surface of theglove to restore the antimicrobial effect when the agent at the exposedsurface has been removed, the glove material comprising by weightpercent:polyvinyl chloride, 43 to 53%; DINP plasticizer, 43 to 53%; CaZnstabilizer, 2.7 to 4.7%; and triclosan, 0.3 to 1.0%, wherein saidtriclosan internal to the glove material will migrate to the surface ofthe glove when said triclosan at the surface of the glove is removed. 6.The glove of claim 5 wherein the weight percentages are:said polyvinylchloride, 48%; said DINP plasticizer, 48%; said CaZn stabilizer, 3.7%;and said triclosan, 0.3%.
 7. The glove of claim 6 wherein said glove isseamless.